minor improvement towards tgenericshardcases

compiler/astalgo.nim

@@ -431,6 +431,9 @@ proc debugTree(n: PNode, indent: int, maxRecDepth: int): PRope =
     appf(result, "$N$1}", [spaces(indent)])
 
 proc debug(n: PSym) =
+  if n == nil:
+    writeln(stdout, "null")
+  else:
     #writeln(stdout, ropeToStr(symToYaml(n, 0, 1)))
     writeln(stdout, ropeToStr(ropef("$1_$2: $3, $4", [
       toRope(n.name.s), toRope(n.id), flagsToStr(n.flags), 

compiler/semexprs.nim

@@ -248,7 +248,11 @@ proc semLowHigh(c: PContext, n: PNode, m: TMagic): PNode =
     of tyInt..tyInt64, tyChar, tyBool, tyEnum, tyUInt8, tyUInt16, tyUInt32: 
       # do not skip the range!
       n.typ = n.sons[1].typ.skipTypes(abstractVar)
-    else: LocalError(n.info, errInvalidArgForX, opToStr[m])
+    of tyGenericParam:
+      # leave it for now, it will be resolved in semtypinst
+      n.typ = getSysType(tyInt)
+    else:
+      LocalError(n.info, errInvalidArgForX, opToStr[m])
   result = n
 
 proc semSizeof(c: PContext, n: PNode): PNode =

compiler/semtypinst.nim

@@ -154,6 +154,7 @@ proc handleGenericInvokation(cl: var TReplTypeVars, t: PType): PType =
       header.sons[i] = x
       propagateToOwner(header, x)
       #idTablePut(cl.typeMap, body.sons[i-1], x)  
+
   if header != nil:
     # search again after first pass:
     result = searchInstTypes(header)
@@ -200,6 +201,9 @@ proc ReplaceTypeVarsT*(cl: var TReplTypeVars, t: PType): PType =
     result = lookupTypeVar(cl, t)
     if result.kind == tyGenericInvokation:
       result = handleGenericInvokation(cl, result)
+  of tyExpr:
+    if t.sym != nil and t.sym.kind == skGenericParam:
+      result = lookupTypeVar(cl, t)
   of tyGenericInvokation: 
     result = handleGenericInvokation(cl, t)
   of tyGenericBody:

compiler/sigmatch.nim

@@ -618,6 +618,9 @@ proc typeRel(c: var TCandidate, f, a: PType): TTypeRelation =
             result = typeRel(c, f.sons[0], a.sons[0])
         else:
           result = isNone
+      else:
+        if a.kind == tyTypeClass:
+          result = isGeneric
         else:
           result = matchTypeClass(c, f, a)
         
@@ -781,6 +784,10 @@ proc ParamTypesMatchAux(c: PContext, m: var TCandidate, f, a: PType,
   of tyExpr:
     if fMaybeExpr.sonsLen == 0:
       r = isGeneric
+    else:
+      if a.kind == tyExpr:
+        InternalAssert a.len > 0
+        r = typeRel(m, f.lastSon, a.lastSon)
       else:
         let match = matchTypeClass(m, fMaybeExpr, a)
         if match != isGeneric: r = isNone